Film developing tank



Dec. 2, 1958 w. F. SCHILLER 2,862,432

FILM DEVELOPING TANK Filed Jan. 29, 1957 2 Sheets-Sheet. 1

Fig. 80 95 Walter F. Schiller IN VEN TOR.

BY arr/M 5% Dec. 2, 1958 w. F. SCHILLER 2,862,432

' FILM DEVELOPING TANK Filed Jan. 29. 1957 2 Sheets-Sheet 2 73 80 Fig I 2 94 95 7/ 8/ 74 9/ 92 26 22 70 72 69 20 90 93 50 40 I I I 56 1: {1 H 80 y l H "as 87 I I I Q2 2 4 1 68 I 44 a & 1" 3 \a 36 77 79 1. 60 89 46 l 62 58 V 64 36 32 g In /02 59 I 1 E 59 5 58 55 a x ,..............=a...., 9 W m3 //4 55 lg 56 54 Fig. 3

Walter F. Schiller IN VEN TOR.

BY WM 29m United States Patent FILM DEVELOPING TANK Walter F. Schiller, Hartford, Conn.

Application January 29, 1957, Serial No. 637,013

2 Claims. c1. sis-90.5

This invention relates to a film developing tank and more particularly to a small, economical tank especially designed for 8 mm. film in roll form.

An object of the invention is to provide a small, economic-al film developing tank which is particularly useful in connection with the development of 8 mm. film and which is economical in that it requires a small quantity of solution, that is, the proper amount for the development of 8 mm. film.

A further object of the invention is to provide a film developing tank which is so constructed that shaking the tank is unnecessary inasmuch as the reels are formed with agitating vanes automatically agitating the developer, solution etc. in response to moving the film from one reel to the other. 7

Another object of the present invention is to provide a small, practical film development tank which is easy to use. The cover for the top of the tank when removed, exposes the entire interior of the'tank so that placing a roll of exposed color or black and white film in the tank involves no difficulty. Thereafter the film is wound on the other reel and the cover is again removed so that the spool on which the exposed film was originally wound may be removed and the development tank reel returned to the tank and operatively connected with an end of the film. Then, after the cover is replaced the solution may be poured through the light trap funnels and the developing process completed, the action differing for black and white and colored film. In either case, though, the film may be developed in daylight, no darkroom being required. I

Another object of the present invention is to provide a practical device of this type which may be produced at a low unit cost and yet which fulfills the need for an effective film developing tank especially designed to care for the needs in developing film. Larger tanks that is, tanks which are universal accommodating film of any size or tanks which are specifically useful in connection with the development of 35 or 16 mm. film do not have the inherent economy of my tank. The reason is that my tank accommodates enough hypo solution, etc. for the development of a 25 foot roll of double-eight mm. film and does not waste the same by extravagant use.

These together with other objects and advantages 'which will become subsequently apparent reside in the Figure 2 is a longitudinal sectional view of the tank in V Figure l; Figure 3 is a sectional line 33 of Figure 2;

Figure 4 is a fragmentary horizontal sectional view through the reels with parts shown in elevation, this view view taken approximately on' the showing principally the threading of the film from one reel to another, and;

Figure 5 is a fragmentary perspective view of one of the reels, parts being shown in section, this view illustrating principally the manner in which the film is attached to the reel.

In the accompanying drawings there is a tank 10 which is constructed in accordance with the principles of the invention. This tank is made of a non-corr-oding mate- ,rial, such as Bakelite or an equivalent substance. The

tank 10 has a bottom wall 12, end walls 13 and 14, together with a front and back wall 15 and 16 respectively. The tank 10 has an open top and is of generally ovalshape. The cover 20 of the tank is made of a top panel 22 with a light trap 24 formed along the edges thereof. This light trap is also a seal and is made by concentric skirts 26 and 28 that are parallel to each other and spaced slightly apart to form a pocket 30. The upper edge of the side walls and end walls of the tank are formed as an upwardly directed U-shape rim with sides 32 and 34 and a pocket 36 therebetween. The pocket accommodates the skirt 28 while skirt 26 fits over the outside surface of the side 32.

There is a light trap pouring spout 40 at one end of the tank. This is made by having the pocket 36' wider, loosely accommodating the side 42 at this point. Defiector plate 44 depends from the inner surface of the .cover 20 adjacent to and parallel to the skirt 42 to further aid in pouring operations and light entrapment. As seen in Figure 2, the enlarged part 36" of the pocket 36 is fitted in relation to the width of side 42 to form a liquid passage 46. The liquid then, flowsthrough this passage and through an outlet opening 48 formed in the cover 20 beneath the shield 50. This shield is ,fixed to the top of the cover .and extends over the opening 48 to deflect the liquid as it is poured from spout 40.

There are two reels 51 and 52 respectively in the tank and each is mounted for rotation on its support 53 and 54 respectively. These supports rise from the bottom 12 of the tank and have support panels 55 and 56 on which the reels '51 and 52 are seated. Centering pins 57 and 58 extend upwardly from the center of the panels 55 and 56 64 respectively along one side wall thereof, and the key is adapted to be drivingly connected to the reels 51 and 52 respectively. Moreover, the upper ends of the keys serve 'as supports for the lower parts 65 and 66 of the light traps 67 and 68 located near the top of the tank.

Light trap 67 has an upper part 69which is made of two rings 70 and 71 respectively, the rings being concentrically with respect to each other and with respect to liquid inlet openings 72. The rings extend downwardly from the inner surface of the cover 20 and are discontinuous whereby there are spaces between the 'arcuate' parts which make up each ring. A funnel 73 is formed of a part of the cover 20 adjacent to the liquid inlet opening 72 by'havingthis part of the cover made of a conical shape and by having an upstanding wall 74 fencing the same. The lower part 65 of the light trap 1 the key 62 allowing the spindle to be rotated by the upper finger knob 80, with respect thereto. This finger knob rises upwardly through the funnel and the -bore' '58 of the spindle may be keyed or made non-circular in order to accommodate crank in addition to the finger knob 80. An enlarged deflector 81 is on the surface of spindle 60 within the liquid entrance opening 72 light trap. Light trap 68 'is constructed identically to the light trap 67 and includes the lower part 66 having bottom wall 85, concentric rings, 86 and 87 rising therefrom in a central opening 89 through which spindle '61passes. The upper part 90 of the light trapi68'has'concentric rings 91 and 92 which depend from funnel 93. There is a central liquid opening 94 in the funnel through which the spindle 61 passes, and a finger-grip or knob 95 also rising upwardly from the tank and through the opening 94 in funnel 93.

Ree1'51 is made of a hub 99 together with an upper and lower side 100 and 101. Upper vanes 102 are on side 100 and lower vanes 103 are on side 101. These vanes function as agitators for the solution as the reel is revolved for the purpose of winding or unwinding film 110. Hub 99 has a film entrance slot 112 and an inner, spring band 114 concentrically arranged therein. The band has protrusions 115 and 116 at one end thereof and protrusions 117 and 118 at the opposite end thereof. The protrusions are adapted to be engaged with notches 118, 119, 120 and 121 respectively which are formed in the side wall of the hub 99 adjacent to the film slot 112. The bias of the spring inner band 114 is such as to tend to maintain the protrusions in engagement with the notches at all times. The spacing of the notches and protrusions are such that the notches in the edges of a 16 mm. film (twin-8 mm.) fit and are engaged therewith when the film is inserted in the film slot 112.

Upper side 100 of the reel 51 has two slots 126 ap-- proximately radially arranged with finger-grips 128 passing therethrough and fixed to the ends of the inner band 114. The purpose of having the finger-grips 128 so arranged is to manually spread the confronting ends of the band away from the hub 99 at the film entrance slot 112 and enabling the film 110 to be attached or separated from the film. Reel 52 is constructed identically.

A support ridge 130 is on the bottom wall 12 of the tank in order to hold the tank level when placed on a supporting surface, as a table. Light window 132 is formed in the front wall 15, and there is a track 134 around the window 130 in which to accommodate the sliding door 136. This door is movable to a position where it covers the light opening 132 or opens the light opening to admit light into the tank, this being necessary during the development of at least some types of black and white film. Film guide pool 138 is mounted for rotation on a vertical shaft 140 which is attached to and which rises from the bottom surface of the tank. Shaft 140 has a bottom spacer 142 on which the spool 138 is mounted for rotation, and it is preferred that the spool have a double taper (Figure l) and small upper and lower flanges to assure that the film will not slip from the spool when it is moved across the light window 132 by properly rotating the reels 51 or 52.

In operation and use of the tank the cover is first removed and one of the reels taken out. The reels, the door, the cover and all other parts are light-proof. A roll of 8 mm. film that has been exposed is inserted on the spindle from which the reel has been removed. The end of the exposed film is attached to the other reel in the tank and the cover is replaced. The film is then wound on the empty reel and the cover again removed. All during this time the door 136 is in the window closing position. The empty spool (supplied with the film) is removed from the tank and the reel, for example reel 52, is returned to the tank and the film inserted and locked to prevent it from pulling off the reel. The cover is again replaced and the solution or other liquid poured into one or both of the tunnels. A measured amount for 8 mm. film passes through the funnels so that there will be no waste.

Now, one reel is turned clockwise while the other is turned counter-clockwise winding the film from one reel to the other and at the same time agitating the liquid in the tank by means of the number of vanes on the reels 51 and 52. It is unnecessary to rock the tank since the agitators on the reel stir the liquid sufiiciently.

For re-exposure the film 110 is placed over the spool 138 and wound from onereel to the other with the window 132 opened allowing light to enter the tank. Moreover, when the type of liquid has to be changed during normal film developing operations, the tank is merely picked up in one hand and emptied by pouring through the spout 40. It is wholly unnecessary to open the tank for the purpose of draining or for the purpose of adding liquid to it.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A film developing tank having side Walls, end walls, bottom and an open top, a cover, a combined light trap and seal separably connecting the edges of said cover to the upper edges of said tank walls, funnels formed 'in said cover and spaced from each other, spindles mounted for rotation in said tank and separable therefrom, said funnels each having an aperture, one of said spindles extending through each aperture and having an outer end for manual rotation, liquid agitating reels, means mounting said reels in said tank for rotation, means drivingly connecting said reels to said spindles, said apertures of said funnels constituting liquid entrances, light traps carried by said cover and said spindles respectively and operatively connected with said funnels to prevent the entry of light through said funnels to the interior of said tank, a pouring spout in said tank and cover, said first mentioned light trap operatively connected with said pouring spout and including an upwardly opening pocket at one edge of one of said walls, a skirt depending from said cover and fitted loosely within said pocket so as to form a liquid passage around said skirt and through said pocket, a deflector plate carried by said cover and located adjacent to said skirt, a pouring spout on said cover, said cover having an opening through which liquid is adapted to pass and in registry with said passage and beneath said pouring spout. I

2. The film developing tank of claim 1 wherein said means mounting said spindles in said tank for rotation include a pair of supports rising from the bottom wall of said tank and having centering pins extending upwardly therefrom, lateral supporting panels attached to said supports and on which fihn reels are adapted to seat, and said spindles having bores within which said centering pins are accommodated thereby mounting said spindles for rotation and oscillation.

References Cited in the file of this patent UNITED STATES PATENTS 2,583,385 Miller Jan. 22, 1952 2,656,773 Wiebalck Oct. 27, 1953.

FOREIGN PATENTS 405,963 Italy Oct. 4, 1943 1,113,161 France Nov. 28, 1955 712,466 Great Britain July 21, 1954 OTHER REFERENCES Popular Photography (Morse 6-3) January 1955, page110. 

